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The maximal lactate steady state (MLSS) is a well-known gold standard method for determining the aerobic capacity of athletic horses. Owing to its high cost and complex execution, there is a search for standardized exercise tests that can predict this value in a single session. One of the methods described for this purpose is the lactate minimum test (LMT), which could be more accurate despite being adequate to predict MLSS. This study aimed to examine the impact of training on the speed corresponding to lactate minimum speed (LMS) and to apply new mathematical methods to evaluate the fitness level of horses based on the curve obtained by the LMT. Ten Arabian horses underwent a 6-week training program based on LMS calculated by second-degree polynomial regression (LMSP). In addition, the LMS was also determined by visual inspection (LMSV), bi-segmented linear regression (LMSBI) and spline regression (LMSS). From the curve obtained during the LMT, it was possible to calculate angles α, ß and ω, as well as the total area under the curve (AUCTOTAL) before (AUCPRELMS) and after (AUCPOSLMS) the LMS. The methods for determining the LMS were evaluated by ANOVA, intraclass correlation coefficient (ICC) and effect size (ES) by Cohen's d test. The Pearson correlation coefficient (r) between the proposed LMS determination methods and other mathematical methods was also calculated. Despite showing a good correlation (ICC >0.7), the LMS determination methods differed from each other (p < 0.05), albeit without a significant difference resulting from conditioning. There were reductions in α:ß ratio, angle α, and AUCPOSTLMS, with the latter indicating lower lactate accumulation in the incremental phase of LMT after conditioning, in addition to an improvement in the animals' aerobic capacity. Considering that the most common methods for determining the LMS are applicable yet with low sensitivity for conditioning assessment, the approaches proposed herein can aid in analyzing the aerobic capacity of horses subjected to LMT. The mathematical models presented in this paper have the potential to be applied in human lactate-guided training program trials with a comparable study basis.

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The association of scanning transmission electron microscopy (STEM) and detection of a diffraction pattern at each probe position (so-called 4D-STEM) represents one of the most promising approaches to analyze structural properties of materials with nanometric resolution and low irradiation levels. This is widely used for texture analysis of materials using automated crystal orientation mapping (ACOM). Herein, we perform orientation mapping in InP nanowires exploiting precession electron diffraction (PED) patterns acquired by an axial CMOS camera. Crystal orientation is determined at each probe position by the quantitative analysis of diffracted intensities minimizing a residue comparing experiments and simulations in analogy to x-ray structural refinement. Our simulations are based on the two-beam dynamical diffraction approximation and yield a high angular precision (∼0.03°), much lower than the traditional ACOM based on pattern matching algorithms (∼1°). We anticipate that simultaneous exploration of both spot positions and high precision crystal misorientation will allow the exploration of the whole potentiality provided by PED-based 4D-STEM for the characterization of deformation fields in nanomaterials.

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RESUMO O presente artigo é uma atualização sobre os principais conceitos, as técnicas, os equipamentos, as lentes e as utilidades do exame de gonioscopia, com foco principal na sua importância para as novas terapias antiglaucomatosas: trabeculoplastia seletiva a laser e cirurgias angulares. Se faz necessária esta revisão e atualização por se tratar de um exame imprescindível para a prática diária do oftalmologista, consolidando o conhecimento necessário para realizá-lo e pelo crescente uso da gonioscopia nas novas terapias antiaglaucomatosas.

ABSTRACT This article is an update on the main concepts, techniques, equipment, lenses, and uses of the gonioscopy exam, with a main focus on its importance for new antiglaucoma therapies: selective laser trabeculoplasty and angular surgeries. This review and update is necessary because it is an essential exam for the daily practice of ophthalmologists, consolidating the knowledge necessary to perform it and because of the increasing use of gonioscopy in new anti-aglaucomatous therapies.

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The Jordan-Schwinger map allows us to go from a matrix representation of any arbitrary Lie algebra to an oscillator (bosonic) representation. We show that any Lie algebra can be considered for this map by expressing the algebra generators in terms of the oscillator creation and annihilation operators acting in the Hilbert space of quantum oscillator states. Then, to describe quantum states in the probability representation of quantum oscillator states, we express their density operators in terms of conditional probability distributions (symplectic tomograms) or Husimi-like probability distributions. We illustrate this general scheme by examples of qubit states (spin-1/2 su(2)-group states) and even and odd Schrödinger cat states related to the other representation of su(2)-algebra (spin-j representation). The two-mode coherent-state superpositions associated with cyclic groups are studied, using the Jordan-Schwinger map. This map allows us to visualize and compare different properties of the mentioned states. For this, the su(2) coherent states for different angular momenta j are used to define a Husimi-like Q representation. Some properties of these states are explicitly presented for the cyclic groups C2 and C3. Also, their use in quantum information and computing is mentioned.

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SUMMARY: For the treatment of trigeminal neuralgia, the foramen ovale is reached by entering the cheek with a needle. Thermocoagulation is performed with balloon compression, administration of alcohol or radiofrequency. Apart from the classical method, it is theoretically possible to reach the foramen ovale through the mouth with the anterior approach. In our study, it was aimed to examine horizontally and vertically the angular values that must be given to the needle to reach the foramen ovale in the anterior approach. Three landmark points were determined on both right and left sides of 25 dry skulls. A rod was inserted starting from these landmark points and passing through the center of the foramen ovale. The vertical and horizontal angular values of this bar were measured. For each foramen ovale, 3 vertical angles, 3 horizontal angles and 4 distance measurements were made. There was a significant difference between the right and left sides in terms of horizontal angular values. Average values of horizontal angles (in degrees); on the right, 7.29 for H1, 12.15 for H2, 32.29 for H3; 1.26 for H1, 9.46 for H2, and 30.56 for H3 on the left side (p<0.005). The angle value was measured as 0 or negative value in 5 (20 %) of the H1 angle measurements made on the right side and 14 (56 %) on the left side. The H2 angle value was found to be smaller than the H1 angle in the skull 2 (8 %) on the right and 3 (12 %) on the left. There was no difference between the right and left sides in terms of vertical angular values. A significant difference was found between the right and left sides in the D1, D2, D4 distances (p<0.005). Six important anatomical features affecting angular values were encountered.

Para el tratamiento de la neuralgia del trigémino, se alcanza el foramen oval introduciendo una aguja en la mejilla. La termocoagulación se realiza con compresión con balón, administración de alcohol o radiofrecuencia. Aparte del método clásico, en teoría es posible alcanzar el foramen oval a través de la cavidad oral mediante el abordaje anterior. En nuestro estudio se tuvo como objetivo examinar horizontal y verticalmente los valores angulares que se deben dar a la aguja para alcanzar el foramen oval en el abordaje anterior. Se determinaron tres puntos de referencia en los lados derecho e izquierdo de 25 cráneos secos. Se insertó una varilla comenzando desde estos puntos de referencia y pasando por el centro del foramen oval. Se midieron los valores angulares verticales y horizontales de esta barra. Para cada foramen oval se realizaron mediciones de 3 ángulos verticales, 3 ángulos horizontales y 4 distancias. Hubo una diferencia significativa entre los lados derecho e izquierdo en términos de valores angulares horizontales. Valores medios de ángulos horizontales (en grados); a la derecha, 7,29 para H1, 12,15 para H2, 32,29 para H3; 1,26 para H1, 9,46 para H2 y 30,56 para H3 en el lado izquierdo (p<0,005). El valor del ángulo se midió como 0 o valor negativo en 5 (20 %) de las mediciones del ángulo H1 realizadas en el lado derecho y 14 (56 %) en el lado izquierdo. Se encontró que el valor del ángulo H2 era menor que el ángulo H1 en el cráneo 2 (8 %) a la derecha y 3 (12 %) a la izquierda. No hubo diferencia entre los lados derecho e izquierdo en términos de valores angulares verticales. Se encontró diferencia significativa entre el lado derecho e izquierdo en las distancias D1, D2, D4 (p<0,005). Se encontraron seis características anatómicas importantes que afectan los valores angulares.

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Anthracnose (ANT) and angular leaf spot (ALS) are significant diseases in common bean, leading to considerable yield losses under specific environmental conditions. The California Dark Red Kidney (CDRK) bean cultivar is known for its resistance to multiple races of both pathogens. Previous studies have identified the CoPv01CDRK/PhgPv01CDRK resistance loci on chromosome Pv01. Here, we evaluated the expression levels of ten candidate genes near the CoPv01CDRK/PhgPv01CDRK loci and plant defense genes using quantitative real-time PCR in CDRK cultivar inoculated with races 73 of Colletotrichum lindemuthianum and 63-39 of Pseudocercospora griseola. Gene expression analysis revealed that the Phvul.001G246300 gene exhibited the most elevated levels, showing remarkable 7.8-fold and 8.5-fold increases for ANT and ALS, respectively. The Phvul.001G246300 gene encodes an abscisic acid (ABA) receptor with pyrabactin resistance, PYR1-like (PYL) protein, which plays a central role in the crosstalk between ABA and jasmonic acid responses. Interestingly, our results also showed that the other defense genes were initially activated. These findings provide critical insights into the molecular mechanisms underlying plant defense against these diseases and could contribute to the development of more effective disease management strategies in the future.

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The objective of this study was to demonstrate the effectiveness of the single transphyseal screw technique in foals diagnosed with carpal valgus deviation. This study included 22 thoroughbred animals of both sexes, with a mean age of 30 days. All animals had a carpal valgus deviation >5° with irregular development of the distal epiphysis of the radius. All animals were surgically treated to correct the carpal valgus deviation by creating a bridge using a single transphyseal screw. Surgical intervention was performed for 40 limbs, comprising 19 right and 21 left thoracic limbs. This corresponded to four animals with carpal valgus deviation >5° in only one of the limbs and 18 with the deviation in both limbs. It was observed that 38/40 treated limbs (95%) achieved normal angulation according to the literature, i.e., angulation between 0° and 5°. No statistical differences were observed between the affected limbs. The single transphyseal screw technique can be used for the correction of carpal valgus deviation in foals. It is indicated in animals with an average age of 30 days (20-55 days), as its main advantages are rapid application, simple execution, and limited trans- and post-surgical complications, making it an effective procedure in thoroughbred foals with carpal valgus angular deviation.

O objetivo do presente estudo foi demonstrar a viabilidade da aplicação da técnica de parafuso único transfiseal em potros, com diagnóstico de desvio valgo do carpo. Foram selecionados 22 animais, da raça PSI, com idade média de 30 dias, de ambos os sexos. Todos os animais apresentavam desvio valgo do carpo acima de cinco graus, com desenvolvimento irregular da epífise distal do rádio. Os animais foram submetidos à cirurgia corretiva para o desvio valgo do carpo por meio da realização de ponte com um único parafuso transfiseal. Foram submetidos à intervenção cirúrgica 40 membros, divididos entre membros torácicos direito e esquerdo 19 e 21, respectivamente, que corresponderam a quatro animais com desvio acima de 5 graus valgo do carpo em apenas um dos membros e 18 animais com o procedimento nos dois membros. Observou-se que 38 dos 40 membros tratados, ou seja, 95%, retornaram a uma angulação considerada normal, entre zero e cinco graus Dois animais apresentaram infecção do implante, de maneira que eles reduziram a angulação, porém não o suficiente para enquadrá-los na angulação normal estabelecida pela literatura. Não houve diferença estatística entre os membros acometidos. A técnica de aplicação do único parafuso transfiseal pode ser indicada para correção do desvio valgo do carpo em potros. Deve ser indicada em animais com idade média de 30 dias (20 a 55 dias de vida), por ter como principais vantagens aplicação rápida, execução simples e com limitadas intercorrências trans e pós-cirúrgicas.

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BACKGROUND: Fiber optic dosimetry (FOD) has emerged as a useful technique that can be used in those cases when intracavitary, real time, high spatial resolution dose assessment is required. Among the several factors characterizing a dosimeter, angular response of FOD probes has to be assessed in order to consider possible clinical application. PURPOSE: The objective of this study was to characterize the angular response of a FOD probe based on a cylindrical shaped YVO4 :Eu3+ scintillator under irradiation with a 6 MV photon beam generated by a linear accelerator (LINAC). METHODS: A FOD probe was irradiated inside a plastic phantom using a 6 MV LINAC photon beam at different azimuthal angles (0° to 360°, 15° steps). Scintillation output was measured with a photomultiplier tube. Similar measurements were performed with a second FOD probe having an optical filter interposed between the scintillator and the fiber. Monte Carlo simulations using PENELOPE were carried out in order to interpret the observed results. RESULTS: The FOD output was symmetrical with respect to the scintillator axis. For the unfiltered probe, the signal was maximum at rear incidence (0°) and steadily decreased down to its minimum value at frontal incidence (180°) having a signal ratio of 37%. The output of the filtered probe showed a plateau from 15° up to 115°. The signal was maximum at 60° and minimum at 180° having a signal ratio of 16%. Monte Carlo simulations predicted symmetry of the deposited dose about 0° and 90°, which contrasts with experimental findings. CONCLUSIONS: Photoluminescence (PL) of the scintillator induced by the Cherenkov light increases the angular dependence. Radiation attenuation inside the scintillator and partial light collection of the scintillation yield by the optical fiber (OF) are responsible for asymmetrical response. Results from this study should be considered in order to minimize angular dependence in FOD.

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OBJECTIVE: The effects of ROM manipulation on muscle strength and hypertrophy response remain understudied in long-term interventions. Thus, we compared the changes in strength and regional muscle hypertrophy after training in protocols with different ranges of motion (ROM) in the seated dumbbell preacher curl exercise using a within-participant experimental design. DESIGN AND METHODS: Nineteen young women had one arm randomly assigned to train in the initial ROM (INITIALROM: 0°-68°; 0° = extended elbow) while the contralateral arm trained in the final ROM (FINALROM: 68°-135°), three times per week over an eight-week study period. Pre- and post-training assessments included one repetition maximum (1RM) testing in the full ROM (0°-135°), and measurement of biceps brachii cross-sectional area (CSA) at 50% and 70% of humerus length. Paired t-tests were used to compare regional CSA changes between groups, the sum of CSA changes at 50% and 70% (CSAsummed), and the strength response between the training protocols. RESULTS: The INITIALROM protocol displayed a greater CSA increase than FINALROM protocol at 70% of biceps length (p = 0.001). Alternatively, we observed similar increases between the protocols for CSA at 50% (p = 0.311) and for CSAsummed (p = 0.111). Moreover, the INITIALROM protocol displayed a greater 1RM increase than FINALROM (p < 0.001). CONCLUSIONS: We conclude that training in the initial angles of elbow flexion exercise promotes greater distal hypertrophy of the biceps brachii muscle in untrained young women. Moreover, the INITIALROM condition promotes a greater dynamic strength increase when tested at a full ROM compared to the FINALROM.

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This study describes a corrective procedure for a metatarsal angular malformation using wedge ostectomy in a 41-day-old Thoroughbred filly. A 41.6 °angular malformation of the metatarsus was corrected with wedge ostectomy of the left hindlimb in association with a type II external fixator and methyl methacrylate resin. The animal was subjected to the surgical procedure under general anesthesia. The filly was placed in dorsal recumbency with the left hind limb free for manipulation. A bone saw was used for the wedge ostectomy, while the bars for external fixation were placed using a drill. A Kirschner pin and acrylic resin were then applied. Radiographic images obtained immediately after surgery confirmed a total malformation reduction of 32.6 (from 41.6° to 9°). With medication and a Robert Jones bandage, intensive postoperative care was instituted to ensure that the animal adapted properly to the linear external fixator without overloading the pins and connection bars. No postoperative complications were observed. On the day after surgery, the filly was standing and walking with no signs of pain. After 180 days, total osseous calcification was achieved, and the implants were removed during the second surgery. The filly demonstrated adequate locomotion, performed all the movements, and ran without any difficulty in the paddock. The remaining discrete angular deviations were partially corrected using hoof trimming.

O objetivo desse estudo é descrever o procedimento de correção da malformação de desvio angular metatársico, utilizando ostectomia em cunha, em uma potra puro-sangue de 41 dias de idade. Uma malformação metatársica angular de 41.6º foi corrigida com a técnica de ostectomia em cunha, em associação com fixador externo tipo II e resina de metilmetacrilato, no membro pélvico esquerdo. O animal foi submetido à cirurgia sob protocolo de anestesia geral. A potra foi posicionada em decúbito dorsal, com o membro pélvico esquerdo livre para manipulação. Para a realização da ostectomia em cunha, foi utilizada uma serra óssea. Para a instalação das barras do fixador externo, uma furadeira foi utilizada e, para fixá-los, pinos de Kirschner e resina acrílica foram aplicados. Logo após a cirurgia, imagens radiográficas foram obtidas para confirmar a redução total de 32,6º (de 41,6º para 9º) de angulação. Para garantir que o animal se adaptasse ao fixador externo linear e não sobrecarregasse os pinos e barras, foram instituídos cuidados pós-operatórios intensos, com medicações e bandagem de Robert Jones. Não houve complicações no pós-operatório. No dia seguinte à cirurgia, a potra estava em pé, caminhando e sem sinais de dor. Após 180 dias, alcançou total calcificação óssea e os implantes puderam ser removidos em um segundo tempo cirúrgico. A potra demonstrou locomoção adequada, realizando todos os movimentos normais e pôde correr pelo pasto sem dificuldades. Um discreto desvio angular remanescente foi parcialmente corrigido por casqueamento.

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Computer vision techniques can monitor the rotational speed of rotating equipment or machines to understand their working conditions and prevent failures. Such techniques are highly precise, contactless, and potentially suitable for applications without massive setup changes. However, traditional vision sensors collect a significant amount of data to process and measure the rotation of high-speed systems, and they are susceptible to motion blur. This work proposes a new method for measuring rotational speed processing event-based data applied to high-speed systems using a neuromorphic sensor. This sensor produces event-based data and is designed to work with high temporal resolution and high dynamic range. The main advantages of the Event-based Angular Speed Measurement (EB-ASM) method are the high dynamic range, the absence of motion blurring, and the possibility of measuring multiple rotations simultaneously with a single device. The proposed method uses the time difference between spikes in a Kernel or Window selected in the sensor frame range. It is evaluated in two experimental scenarios by measuring a fan rotational speed and a Router Computer Numerical Control (CNC) spindle. The results compare measurements with a calibrated digital photo-tachometer. Based on the performed tests, the EB-ASM can measure the rotational speed with a mean absolute error of less than 0.2% for both scenarios.

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The common bean (Phaseolus vulgaris L.) is the most important grain legume in the human diet, mainly in Africa and Latin America. Argentina is one of the five major producers of the common bean in the world, and the main cultivation areas are concentrated in the northwestern provinces of this country. Crop production of the common bean is often affected by biotic factors like some endemic fungal diseases, which exert a major economic impact on the region. The most important fungal diseases affecting the common bean in Argentina are white mold caused by Sclerotinia sclerotiorum, angular leaf spot caused by Pseudocercospora griseola, web blight and root rot caused by Rhizoctonia solani, which can cause production losses of up to 100% in the region. At the present, the most effective strategy for controlling these diseases is the use of genetic resistance. In this sense, population study and characterization of fungal pathogens are essential for developing cultivars with durable resistance. In this review we report diversity studies carried out on these three fungal pathogens affecting the common bean in northwestern Argentina, analyzing more than 200 isolates by means of molecular, morphological and pathogenic approaches. Also, the screening of physiological resistance in several common bean commercial lines and wild native germplasm is reviewed. This review contributes to the development of sustainable management strategies and cultural practices in bean production aimed to minimize yield losses due to fungal diseases in the common bean.

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Coronary artery disease (CAD) is among the leading causes of death worldwide. Initial studies require an electrocardiogram stress test often followed by cardiac imaging procedures. However, conventional indices still show insufficient diagnostic performance. We propose quaternion methods to evaluate abnormal alterations during ventricular depolarization and repolarization. Assessment was conducted during a Bruce protocol treadmill stress test and after the end of the exercise. We developed an algorithm to automatically determine the beginning and end of exercise and then, computed the angular and linear velocities. Statistical analysis for feature selection and classification between ischaemic and non-ischaemic patients was used. The most significant markers were maximum linear velocity during ventricular depolarization (p < 5E-9) and maximum angular velocity during the second half of the repolarization loop (p < 5E-16). The latter reached sensitivity / specificity pair of 78 / 92 (AUC 0.89). A linear classifier showed a trend of reduction in cardiac vector velocity in at-risk patients after the end of exercise. The sensitivity / specificity pair reached was 86 / 100. Trajectory deviations of depolarization / repolarization loops that result from ischaemia effects, could be responsible for the observed reduction in dynamic changes during exercise. Further studies could provide non-invasive complementary tools to detect CAD risk. Graphical abstract This data is mandatory, please provide.

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We consider a quantum spinless nonrelativistic charged particle moving in the xy plane under the action of a time-dependent magnetic field, described by means of the linear vector potential A=B(t)-y(1+α),x(1-α)/2, with two fixed values of the gauge parameter α: α=0 (the circular gauge) and α=1 (the Landau gauge). While the magnetic field is the same in all the cases, the systems with different values of the gauge parameter are not equivalent for nonstationary magnetic fields due to different structures of induced electric fields, whose lines of force are circles for α=0 and straight lines for α=1. We derive general formulas for the time-dependent mean values of the energy and magnetic moment, as well as for their variances, for an arbitrary function B(t). They are expressed in terms of solutions to the classical equation of motion ε¨+ωα2(t)ε=0, with ω1=2ω0. Explicit results are found in the cases of the sudden jump of magnetic field, the parametric resonance, the adiabatic evolution, and for several specific functions B(t), when solutions can be expressed in terms of elementary or hypergeometric functions. These examples show that the evolution of the mentioned mean values can be rather different for the two gauges, if the evolution is not adiabatic. It appears that the adiabatic approximation fails when the magnetic field goes to zero. Moreover, the sudden jump approximation can fail in this case as well. The case of a slowly varying field changing its sign seems especially interesting. In all the cases, fluctuations of the magnetic moment are very strong, frequently exceeding the square of the mean value.

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Las fracturas del radio distal están entre las patologías más comunes en el área de la emergencia, actualmente los tratamientos más utilizados son la fijación con alambres de Kirschner y fijador externo (AKFE), o la osteosíntesis con placas volares de estabilidad angular (PVEA), realizamos un estudio comparativo de los resultados a corto plazo entre ambos métodos. Se realizó un estudio transversal, retrospectivo y descriptivo desde el 2005 al 2019, donde se revisaron las historias de los pacientes con fracturas de radio distal tratados con AKFE o PVEA, evaluando el alta después de la medición de la amplitud de movimiento articular funcional. Se incluyeron 68 pacientes, 47(69,11%) pacientes tratados con PVEA y 21(30,88%) con AKFE, la edad promedio fue de 53,07 años, la causa más común fue la caída de su altura en 60,29% casos, el alta médica por mejoría se realizó a las 15,95 semanas para AKFE y a las 9,86 semanas para PVEA (<0.05). La osteosíntesis con PVEA evidenció un menor tiempo de recuperación de la amplitud de movimiento articular con respecto a los pacientes tratados con AKFE(AU)

Fractures of the distal radius are among the most common pathologies in the emergency area, currently the treatment more frequently used are fixation with Kirschner wires and external fixator (KWEF), or osteosynthesis with angular stability volar plates (FAVP), we carried out a comparative study of the short-term results between both methods. This is a cross-sectional, retrospective and descriptive study from 2005 to 2019, where the histories of patients with distal radius fractures treated with KWEF or FAVP revised, evaluated, evaluating at discharge after functional joint range of motion was measured.68 patients were evaluated, 47 patients treated with FAVP and 21 with KWEF, average age of 53.07 years, the most common cause was the fall from his height with 60.29%, the medical discharge was made at 15,95 weeks for KWEF and 9,86 weeks for FAVP; with a t student<0.05 between them. Osteosynthesis with FAVP evidenced a shorter recovery time for joint range of motion compared to patients treated with KWEF(AU)

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Growth modulation (GM) with tension-band plates (TBPs) by tethering part of the growth plate is an established technique for the correction of angular deformities in children, and it has increasingly supplanted more invasive osteotomies.Growth modulation with TBPs is a safe and effective method to correct a variety of deformities in skeletally immature patients with idiopathic and pathological physes. The most common indication is a persistent deformity in the coronal plane of the knee exceeding 10°, with anterior and/or lateral joint pain, patellofemoral instability, gait disturbance, or cosmetic concerns. GM has also shown good results in patients with fixed flexion deformity of the knee and ankle valgus.This paper reviews the history of the procedure, current indications, and recent advances underlying physeal manipulation with TBPs. Cite this article: EFORT Open Rev 2021;6:658-668. DOI: 10.1302/2058-5241.6.200098.

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Abstract Introduction Persistent postural-perceptual dizziness (PPPD) is a functional vestibular disorder characterized by chronic dizziness, unsteadiness, and hypersensitivity to motion. Preexisting anxiety disorders and neurotic personality traits confer vulnerability to PPPD. High anxiety during acute vertigo or dizziness incites it. A functional magnetic resonance imaging (fMRI) study of chronic subjective dizziness found unexpectedly hypoactive responses to vestibular stimulation in cortical regions that integrate threat assessment and spatial perception. Objective This fMRI study used non-moving, but emotionally charged visual stimuli to investigate the brain's activity of PPPD patients and control subjects. Methods The participants included 16 women with PPPD and 16 age-matched women who recovered completely from acute episodes of vertigo or dizziness capable of triggering PPPD. Brain responses to positive, neutral, and negative figures from the International Affective Picture System were measured with fMRI and compared between the groups. Dizziness handicap, anxiety, and depression were assessed with validated questionnaires. Results Between group analyses: Participants with PPPD showed reduced activity in anterior cingulate cortex and increased activity in left angular gyrus in response to negative versus positive stimuli, which was not observed in recovered individuals. Within group analyses: Participants with PPPD had increased activity in visuospatial areas (parahippocampal gyrus, intraparietal sulcus) in negative versus positive and negative versus neutral contrasts, whereas recovered individuals had increased activity in anxiety regions (amygdala, orbitofrontal cortex). Conclusion Patients with PPPD may be more attuned to spatial elements than to the content of emotionally charged visual stimuli.

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Introduction Persistent postural-perceptual dizziness (PPPD) is a functional vestibular disorder characterized by chronic dizziness, unsteadiness, and hypersensitivity to motion. Preexisting anxiety disorders and neurotic personality traits confer vulnerability to PPPD. High anxiety during acute vertigo or dizziness incites it. A functional magnetic resonance imaging (fMRI) study of chronic subjective dizziness found unexpectedly hypoactive responses to vestibular stimulation in cortical regions that integrate threat assessment and spatial perception. Objective This fMRI study used non-moving, but emotionally charged visual stimuli to investigate the brain's activity of PPPD patients and control subjects. Methods The participants included 16 women with PPPD and 16 age-matched women who recovered completely from acute episodes of vertigo or dizziness capable of triggering PPPD. Brain responses to positive, neutral, and negative figures from the International Affective Picture System were measured with fMRI and compared between the groups. Dizziness handicap, anxiety, and depression were assessed with validated questionnaires. Results Between group analyses: Participants with PPPD showed reduced activity in anterior cingulate cortex and increased activity in left angular gyrus in response to negative versus positive stimuli, which was not observed in recovered individuals. Within group analyses: Participants with PPPD had increased activity in visuospatial areas (parahippocampal gyrus, intraparietal sulcus) in negative versus positive and negative versus neutral contrasts, whereas recovered individuals had increased activity in anxiety regions (amygdala, orbitofrontal cortex). Conclusion Patients with PPPD may be more attuned to spatial elements than to the content of emotionally charged visual stimuli.

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Hummingbirds are perhaps the most exquisite bird species because of their prominent iridescence, created by stacks of melanosomes in the feather barbules. The feather colours crucially depend on the nanoscopic dimensions of the melanosome, and the displayed iridescence can distinctly vary, dependent on the spatial organization of the barbs and barbules. We have taken the genus Coeligena as a model group, with species having feathers that strongly vary in their spatial reflection properties. We studied the feather morphology and the optical characteristics. We found that the coloration of Coeligena hummingbirds depends on both the Venetian-blind-like arrangement of the barbules and the V-shaped, angular arrangement of the barbules at opposite sides of the barbs. Both the nanoscopic and microscopic organization of the hummingbird feather components determine the bird's macroscopic appearance.

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Introducción: la extracción del cristalino transparente en pacientes con cierre angular primario se plantea si existe presión intraocular mayor o igual que 30 mm Hg o daño por glaucoma. En ojos con elevación moderada de la presión intraocular se desconocen los resultados. Objetivo: evaluar la influencia de la presión intraocular preoperatoria en el control del cierre angular primario tratado con extracción del cristalino transparente. Material y Métodos: se realizó un estudio pre-experimental, entre enero de 2013 y enero de 2020, incluyó 78 ojos de 78 pacientes con cierre angular primario tratados con extracción del cristalino transparente; divididos en dos grupos según presión intraocular preoperatoria. Para el análisis estadístico se empleó chi cuadrado de independencia, probabilidad exacta de Fisher, prueba t para muestras independientes y análisis de varianza de medidas repetidas; con significación estadística del 95 por ciento. Resultados: hubo diferencias significativas entre ambos grupos para longitud axial (p=0,003), grosor del cristalino (p<0,001) y espesor corneal central (p=0,016). La presión intraocular y número de colirios, variaron de forma muy significativa (p<0,001) entre el pre y posoperatorio, y entre ambos grupos en los diferentes momentos analizados. En el grupo A el 94,4 por ciento de los ojos mostró control absoluto posoperatorio invariable en el tiempo, en el grupo B la mayoría de los ojos tuvo control relativo con diferencias muy significativas (p<0,001) entre ambos. Conclusiones: la presión intraocular preoperatoria influye en el control del cierre angular primario tratado con extracción del cristalino transparente; valores previos menores que 30 mm Hg, propician mejor control posoperatorio(AU)

Introduction: Clear lens extraction is considered in patients older than 50 years with primary angle closure and intraocular pressure greater than or equal to 30 mm Hg or damage due to glaucoma. The results are unknown in eyes with a moderate elevation of intraocular pressure. Objective: To evaluate the influence of preoperative intraocular pressure in the control of the primary angle closure treated with clear lens extraction. Material and Methods: A pre-experimental study was conducted between January 2013 and January 2020. It included a total of 78 eyes of 78 patients with primary angle closure treated with clear lens extraction. They were divided into two groups according to preoperative intraocular pressure. For statistical analysis, Chi-square test, Fisher's exact probability test, and t test were used for independent samples and analysis of variance with repeated measurements; with 95 percent statistical significance. Results: There were significant differences in axial length (p=0,003), lens thickness (p<0,001) and central corneal thickness (p=0,016) between both groups. Intraocular pressure and the number of eye drops varied very significantly (p<0,001) between the pre-and postoperative periods and between both groups at the different moments analyzed. In group A, 94,4 percent of the eyes showed absolute postoperative control, which remained unchanged over time. In group B, most eyes had relative control. There were very significant differences (p<0,001) between both groups. Conclusions: Preoperative intraocular pressure influences the control of primary angle closure treated with clear lens extraction; previous values less than 30 mm Hg favor better postoperative control(AU)

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